1. Field of the Invention
The present invention relates to a driving tool equipped with a rechargeable battery pack as a power source, for example, a gas combustion type driving tool for driving nails.
2. Description of the Related Art
For instance, as a driving tool such as a nail driver, a gas combustion type driving tool, which strikes driven members by reciprocating a piston with gases exploded in a combustion chamber, has been proposed as well as a driving tool using compressed air as a driving source. In the case of this gas combustion type driving tool, a fan is provided in a combustion chamber in order to stir the gases supplied into the combustion chamber and air introduced from outside to the combustion chamber in an appropriate ratio or to accelerate evacuation from the combustion chamber after combustion (after striking driven members). This fan in the combustion chamber rotates with an electric motor as a drive source. This electric motor for driving the fun in the combustion chamber uses, for example, a rechargeable battery pack as a power source, and this battery pack is detachably attached in the vicinity of a handle portion of the driving tool.
In an electric driving tool equipped with a detachable battery pack for charging etc. as described above, various technologies have been proposed regarding a structure for attaching this battery pack to a tool main body side, as provided, for example, in Japanese Laid-Open Patent Publication No. 10-296660, Japanese Laid-Open Patent Publication No. 2004-1193, and Japanese Laid-Open Patent Publication No. 2003-297312. Most of these technologies in the art relate to an electric tool to which substantially fixed and comparatively small vibration is consecutively applied during the use of an electric drill and an electric screwdriver etc., and special measures for the battery pack against the vibration are not required. Further, in Japanese Laid-Open Patent Publication No. 2004-1193, a technology is described regarding a gas combustion type driving tool in which a large vibration or impact is applied to the main body as a force of reaction each time a striking movement is made (intermittently).
However, the technology described in Japanese Laid-Open Patent Publication No. 2004-1193 is to prevent an electric contact failure against terminal blocks of the battery pack, which is caused by the vibration etc. occurred each time a striking movement is made to the tool body. Therefore, it is required to reliably prevent other failures (for example, falling of the battery pack etc.) caused by the vibration etc.
Thus, there is a need in the art to prevent various failures predicted to occur by a large vibration or impact caused each time a striking movement is made in a driving tool equipped with a detachable battery pack as a power source such as a gas combustion type nail driver etc.